The binomial naming system
Key definition
Linnaeus gave every species of living organism two names, written in Latin. This is called the binomial system. The first name is the name of the genus the organism belongs to, and always has a capital letter. The second name is the name of its species, and always has a small letter. This two-word name is called a binomial. For example, a wolf belongs to the genus Canis and the species lupus. Its binomial is Canis lupus. These names are printed in italics. When you write a Latin name, you cannot write in italics, so you should underline it instead. The genus name can be abbreviated like this: C. lupus.
species – a group of organisms that can reproduce and produce fertile offspring binomial system – an internationally ageeed system in which the scientific name of an organism is made up of two parts showing the genus and species
Study tip Do take care to write Latin names (binomials) correctly. You will often see them written wrongly in the media! You should always use a capital letter for the first name and a small letter for the second name.
Question 1.1 The table shows how two organisms – a monarch butterfly and a giant pangolin – are classified. a Use the informatiton in the table to suggest whether these two organisms are not related at all, distantly related or closely related. Explain how you made your decision. b Write down the genus of the giant pangolin. c Use the Internet or a textbook to find out how a human is classified. Write it down in a table like the one shown on the right.
Kingdom
animal
animal
Phylum
arthropods
vertebrates
Class
insects
mammals
Order
Lepidoptera Pholidota (butterflies and moths)
Family
Danaidae
Manidae
Genus
Danaus
Manis
Species
Danaus plexippus
Manis gigantea
Monarch butterfly
Giant pangolin
Original material © Cambridge University Press 2014
Chapter 1:
Classification
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